Chemical agent monitors are known to be used for detection of chemical warfare agents for battlefield, for environmental clean-up, for treaty monitoring and verification missions, and for other purposes, where harmful chemicals contained in the air (alarm molecules) are to be detected.
Mostly, the chemical agent monitors are Ion Mobility Spectrometry (IMS)-based apparatuses. For instance, known in the art, the Chemical Agent Monitor (CAM) is employed by several armies as a reliable system for the above-described purposes.
The Improved Chemical Agent Monitor (ICAM) maintains the performance characteristics of the CAMs but has an improved design which is more reliable and maintainable. As a hand-held surface monitor, the ICAM is unequaled; however, it monitors only one class of chemical at a time (nerve or blister), and it cannot be used as an unattended point detector.
Besides, after an ICAM detects alarm molecules, the residual alarm molecules must be removed before the unit is ready for a subsequent detection operation. The alarm molecule removal is referred to as a "clear-down." In order to remove the alarm molecules, the ICAM is provided with charcoal filter caps, which are manually positioned over the ICAM's inlet and exhaust parts to speed the clear-down. The charcoal filter removes residual alarm molecules from the exhausting air thereby producing clean air (or filtered air) which is directed to the ICAM's inlet port. The filtered air passes through the ICAM, displaces the remaining alarm molecules and, as a sequence, clears down the ICAM more rapidly.
Disadvantageously, this method of clearing the ICAM down involves manual involvement of an operator after each challenge, and therefore, is inconvenient and time and labor consuming.
It would be highly desirable to provide a chemical agent monitor with automatic clear-down after each challenge thereby avoiding an operator involvement.